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Earth Explorer is an online source of news, expertise and applied knowledge for resource explorers and earth scientists. Sponsored by Geosoft.


News & Views

News Archive

December 7, 2016

Geosoft introduces IP and resistivity inversion in VOXI Earth Modelling

Geosoft has added induced polarization and resistivity data inversion to its VOXI Earth Modelling 3D inversion software service. Geoscientists are now able to create detailed 3D models of conductivity and chargeability from IP and resistivity survey data with VOXI. The resulting models can assist in interpreting and targeting regions for mineral and environmental applications...

December 5, 2016

Mexico's Deepwater Round Exceeds Expectations

Some of the world's biggest oil companies showed up Dec. 5 and agreed to invest on the Mexican side of the Gulf of Mexico, proving that deepwater exploration still has a pulse despite challenging market conditions...

November 30, 2016

Magnetic inversion results for Ngamiland available for download

A regional-scale geophysical inversion of magnetic field data in the Ngamiland region of northwestern Botswana is now available for download from the Botswana Geoscience Portal, a partnership initiative of the Botswana Geoscience Institute, industry sponsors and Geosoft...

November 30, 2016

LIGO Resumes Search for Gravitational Waves

After a series of upgrades, the twin detectors of LIGO, the Laser Interferometer Gravitational-wave Observatory, have turned back on and resumed their search for ripples in the fabric of space and time known as gravitational waves. LIGO transitioned from their engineering test runs to full science observations at 8 a.m. Pacific Standard Time on November 30...

November 9, 2016

International Volcano Scientists Unite

For the first time, the United States will host the international Volcano Observatory Best Practices workshop, previously held only in Italy. The workshop will take place this month in Vancouver, Washington. It is designed specifically for volcano observatories around the world and their staff to exchange ideas and best practices with each other...

October 4, 2016

USGS Assesses Mineral Potential for Sagebrush Habitats in Six Western States

USGS has completed a comprehensive assessment and inventory of potential mineral resources covering approximately 10 million acres of Federal and adjacent lands in Idaho, Montana, Nevada, Oregon, Utah and Wyoming...

October 3, 2016

Uganda Targets Up to U.S.$100 Million for Mineral Exploration

Uganda is well endowed with mineral resources and, like many naturally-gifted African countries, is becoming keen on ensuring that these resources play a transformative role in its long-term structural transformation dream - the Vision 2040...

September 9, 2016

Small-Scale Fishers Get A Big Boost With First-Of-Its Kind Impact Investment Fund

Conservation organization Rare announces the Meloy Fund for Small-Scale Fisheries at Our Ocean Conference. The Global Environment Facility, one of the largest funders of conservation worldwide, will be investing $6 million into the fund...

September 1, 2016

Scientists take to the skies to track West African pollution

Scientists operating research aircraft over West Africa have detected organic materials in the atmosphere over a number of urban areas, contributing to concerns of the rise in pollution across the region...

August 17, 2016

New IGS Xplore prospectivity maps for Botswana

International Geoscience Services have released a series of base metal prospectivity maps for the Ngamiland District of northwestern Botswana using free geodata available on the recently-launched Botswana Geoscience Portal, hosted by Geosoft. The maps identify favorable areas for copper, zinc and lead mineralization using geological, geochemical and geophysical datasets downloaded directly from the portal.

August 11, 2016

NexGen Makes New High Grade Discovery

NexGen Energy reported the discovery of a new high grade zone of mineralization 4.7 km northeast of the Arrow Deposit as part of an on-going summer drilling program on its 100% owned, Rook I property, Athabasca Basin, Saskatchewan...

August 10, 2016

Rampion UXO Disposal to Take Place This Week

E.ON has confirmed that the two unexploded devices, detected along the Rampion offshore cable route will be safely disposed this week following the consultation with the Marine Management Organisation...

August 9, 2016

Diamonds In The Rough: E&Ps Find New Reserves In Mature Basins

The oil industry’s history demonstrates clearly that new plays and prospects have long been found in mature basins that were thought to be well on the way to being squeezed dry. Through the acquisition of new data, developing new concepts and coming up with fresh interpretations, long-producing basins around the world from the North Sea to Malaysia have continued to reveal new riches...

August 8, 2016

Northern Shield Identifies High Quality VTEM Targets at Séquoi

Northern Shield Resources announced the results of the interpretation and modelling of the VTEM survey from the Séquoi Property in the Labrador Trough of Quebec . Séquoi is owned 100% by Northern Shield and is being explored for Noril'sk style Ni-Cu-PGE massive sulphides. After geophysical modelling and interpretation of the VTEM data from Séquoi, six VTEM anomalies of significant interest have been identified...

August 3, 2016

Rio Tinto tailors big data drive to copper

Rio Tinto will put the weight of an exploration big data push and its newly-formed Growth and Innovation group behind its desire to identify a "tier 1" copper asset. Speaking at the annual Diggers & Dealers conference in Kalgoorlie, Growth and Innovation group executive Stephen McIntosh said Australia was "overdue for a tier 1" mineral discovery of any type...

August 1, 2016

Tetra Tech Awarded $200 Million Navy CLEAN Contract

Tetra Tech announced that it has been awarded a $200 million, single-award contract by Naval Facilities Engineering Command (NAVFAC) Atlantic. Through the Comprehensive Long-term Environmental Action Navy (CLEAN) contract, Tetra Tech will provide environmental engineering support services to installations within the NAVFAC Atlantic Area of Responsibility...

May 3, 2016

NATO Science for Peace and Security (SPS), MODUM Partners announce "Young Scientist Summer School on Sea Dumped Chemical Weapons"

This international project cooperates closely with CHEMSEA (Search and Assessment of Chemical Weapons) Project for and sharing and knowledge transfer...

April 12, 2016

Monday mad rush for gold stocks

Renewed optimism about the outlook for gold saw investors pile back into gold stocks, pushing many stock to 52-week highs in heavy volumes...

April 11, 2016

Medgold Resources: Continues to Expand the Boticas Gold Project, Portugal; Proposes $200,000 Private Placement

Medgold Resources is pleased to announce new assay results from contiguous rock-chip sampling from the Limarinho South zone at its Boticas gold project in Portugal, which include a highlight of 6.0m @ 5.7 g/t Au...

April 8, 2016

De-carbonizing our energy sector

Nuclear energy currently provides around 11 percent of the world's electricity. China, the European Union, the United States, India, Russia, South Korea, and other nations’ have major existing fleets...

April 1, 2016

Follow-Up Drilling Results Indicate Wide Gold Zones at Hendricks Gold Discovery

Gascoyne Resources Limited announced that it has received the final assay results from the 10,000 metre aircore exploration drilling programme...

March 26, 2016

The Oil Market Is Finally Hitting Its Breaking Point

After a significant reduction in investments over the past two years, oil companies can no longer overcome the production declines from legacy wells...

March 15, 2016

N-Sea Expands into the French Offshore Wind Industry

Subsea IMR provider, N-Sea, has signed a letter of intent with CERES Recherches & Expertise Sous-Marine and TechSub Industrie Environement, to provide subsea survey, installation and remediation services to the French offshore wind industry...

March 9, 2016

PDAC 2016 Convention Exceeds 22,000 Attendees

Optimism and opportunity abounded at the PDAC 2016 Convention of The Prospectors & Developers Association of Canada in spite of recent industry challenges...

March 3, 2016

6 Alpha Launches EOD Contracting Division

6 Alpha Associates, a specialist risk consultancy practice, with expertise in the assessment and management of unexploded ordnance, has launched a dedicated explosive ordnance disposal division...

Quick, find me a target

In a rush to drill based on chasing anomalies, explorers may overlook the structural geology and miss the best drill spots.

by Graham Chandler on June 4, 2012 applied

When geophysicist Hernan Ugalde was contracted by a junior mining company to help define drilling targets, he thought himself fortunate the company had an exploration vice president who believed there was more to it than choosing purple anomalies on remote sensing maps.

“It was an iron exploration project in [Canada’s] Northwest Territories,” recalls the Senior Consulting Geophysicist at Toronto-based Paterson, Grant & Watson Limited. The mining company had flown the magnetics, planning to use map anomalies for direct detection of iron deposits. Since iron is magnetic then the large anomalies should be important targets, went the reasoning. Ugalde and the VP Exploration examined the magnetic data, but to improve confidence, recommended ground field work follow-up. It was fortunate they did. “The field work recognized that the Fe-formation was hematite, which is non-magnetic,” says Ugalde. “Instead of throwing out the data and claiming that the survey didn’t work, we used a think-out-of-the-box approach and modeled 2D sections.” He says working with a structural geologist helped him to separate what was geologically reasonable from what wasn’t. “We ended up with very detailed models that provided the company with targets, on which they will be following up this year.”

The episode points up a valuable lesson for mining companies intent on launching a drilling program in short order after looking at remote sensing data alone; which often happens when eager investors want to see some action.

Ugalde suggests starting from the regional, then going into more detail. He stresses the importance of field work, mapping and measurement of rock properties by the geologist and geophysicist, who should work in tandem. He says in the NWT example "without that, we wouldn't have been able to recognize the different geological units that were the base of the model, instead of the usual blocks with no geological interpretation."

Key is to take time for the geology. “The main challenge is to get the message beyond the ‘can you find me a target?’ stage,” says Ugalde. “It is quite common to see a mining company operating with only one geologist, who is either too busy dealing with all the admin and raising funds, or doesn’t have the background to know what to expect from geophysics.”

Some numbers help drive home his point. “Airborne geophysics with 50 metre line spacing typically provides a resolution of just 10 metres per pixel making definition of precise drilling targets difficult,” he says. “However, once you can make the company understand the value behind the data beyond the drilling frenzy (i.e. extensive structural and lithogical delineation on areas where access is difficult and/or have not been mapped completely), they realize that there is great value in doing this kind of remote sensing mapping.”

The big picture is often overseen. “When companies jump stages on the large-to-small-scale approach, they sometimes lose track of what factors they did use to filter in/out some areas and often end up making an inefficient use of resources,” says Ugalde. “There is a big rush to produce an NI 43-101 [national instrument for the Standards of Disclosure for Mineral Projects within Canada] with proven/inferred reserves.” It requires sampling—drilling—at 50 m, and in the rush to comply, Ugalde says it’s not uncommon that structure is overseen and therefore boreholes are placed where there shouldn’t be any, or at an inefficient attitude/geometry. “To give you an idea, I have seen projects with <100 km of drilling where the general structure was totally overseen, but once you plotted the grades it was quite evident that there was a structural control (folding).” Taking some extra time to analyze the structure would have definitely improved the efficiency of that large drilling program.

In the specific case of geophysics, results can be misleading unless the whole story behind them is addressed. For example, “if borehole planning is based on the wrong information (e.g. K-anomalies associated to lithology instead of alteration; not addressing magnetic inclination and/or remanence; overseeing that in an alteration zone you are interested in the magnetic low around the large purple “blob”), then you’re missing the whole story and this can lead to the waste of those boreholes,” says Ugalde. “It’s easy to just say geophysics did not work, rather than understanding the overall fit.”

Chris Vose, CEO of Brisbane-based Murrumbo Limited, has seen it directly from the explorer side. “In my experience of small cap explorers, there is way too much drilling before there is any understanding of geoscience,” he says. “Shareholders buy on rumor and sell on fact and there is a perception that ‘drilling equals rumor’ and the day traders and punters pump the stock when drilling is underway and results are pending.” He considers the rush to drill is driven by a financial imperative: explorers often lack the ability to communicate their exploration strategy without delivering some headline results for shareholders and investors.

Vose says that as a CEO and engineer he relies upon geoscientific information and advice and often finds geologists differ on their interpretations. “I think that what good geologists do well is to gather evidence before advancing a theory or a model,” he says. “In particular geophysics, geochemistry, structural geology and geochronology are critical to finding mineralisation.”

Though not a junior investment situation, Ugalde uses another example of the value of ground control when interpreting geophysical data: the Bathurst Mining Camp. A producing mine from the 1950s, it was pretty much closed and the Geological Survey of Canada (GSC) funded a new survey; new geophysics. He describes the entire area as 60 x 60 km with very few outcrops. “So we had lots of geophysics but little matching ground control,” he recalls.

“We did some modeling of gravity and magnetic data, in 2D sections. The key here was having me working together with Cees van Staal, GSC’s structural geologist who knew the way the faults were dipping, and how many folded sequences did we need to put on.” Combining van Staal’s knowledge of the area with the resolving power of geophysics, they ended up not only with a great 3D model based on geophysics, but one that made geological sense too.

“The geological input from Cees was invaluable,” says Ugalde. “Modeling is a non-unique problem, so you can put an infinite number of geometries and still fit the data. Having someone who knew what was feasible and what wasn’t was very important.”

Software plays a big role but needs to be applied properly, cautions Ugalde. “We have software that makes life way easier and that almost anyone can operate,” he says. “However, knowing how to use the software is not a replacement for knowing what you are doing from the geoscience perspective.” While a powerful aid, he sees a trend where available software is not being used to its full potential, mostly because of a lack of control on what is actually being done or what is the overall goal. “More access to sophisticated tools needs to be balanced with proper training and field experience.”

To help provide this balance it’s equally important from the software development perspective to ground advanced geocomputing with the right geoscience. Software developer and former exploration geophysicist, Ian MacLeod, Chief Technologist at Geosoft, explains the approach. “We rely strongly on the expertise of our senior scientists, working with industry collaborators, to build and develop new technologies. Impactful technology (based on our experience and understanding of what is proven and effective for exploration) is more important than pushing out the latest feature set.”  

“Good technology accelerates labor intensive routines,” says MacLeod, “and it aids in the integration and visualization of the many dimensions of exploration - geology, geochemistry, geophysics, remote-sensing, field mapping, drilling - to help an explorer iterate and best understand their target environment. But proper understanding of all that data, and correct application of the tools, requires sound geological thinking and practical experience.”

What can be done to remedy the lack of interest in ground structural mapping as a geophysics follow-up? Lots of training and going back to basics, figures Ugalde. “We need geologists to understand more about geophysics so that in the future they know what to ask for and what are the limitations of each methodology based on geology, survey specifications etc,” he says. And conversely, “we need to train geophysicists to understand more about geology and see how geological processes affect rock properties and therefore the observed signature.” There’s a need for geologists to go back to basics too. “How many companies are there that actually do structural mapping as part of their standard exploration?” questions Ugalde. “How many companies take the time to build a geological model, rather than just grid the reserves?”

It’s not just software training he reckons, but knowing what to do with the data. “For that, we need to train people at all levels: university level (before graduation), and the current professionals doing the operations.”

Training at the university level is not a simple one he says. Ugalde has completed a PhD so has some firsthand observations. “Universities now have a mandate for self-sufficiency which has led them to teach programs that are more attractive for undergrad students, who are the ones who bring more money (tuition) into the departments,” he says. The result is that more and more geology departments are walking away from hard-rock geology and switching to environmental-based programs because that is what sells to students. “However, nobody bothers explaining to students what kind of jobs they can get with that background,” he says. “For example, talk to a second year undergraduate about a career in mining, he/she will probably refuse because of the bad reputation of non-environmentally-friendly mining.”

Indeed, judging from some recent group discussion on LinkedIn, many geologists are seeing this: a declining trend in hard-rock geology in universities. The trendy shifts today are increasingly on environmental studies, carbon debates, sustainable energy—which need to be explored too—but it is seen as significantly affecting the exploration industry. Structural mapping seems to be on the decline; some consultants are encountering exploration companies which even consider it a waste of time and money. But basic structural mapping by experienced people using the newest technologies should still be seen as a highly cost-effective exploration method.

University co-op programs can work well says Ugalde. Under these, students combine regular university terms with time working in the industry; it exposes them to real problems using real tools. But also “we definitely need to motivate more cross-training (geophysics for geologists; geology for geophysicists) in the industry,” he adds, “so that we develop a common language and everyone is clear on what to get from the data, and what kind of data to use on each situation.”

It may take a while to evolve, but ultimately exploration companies and their investors will realize the value of good structural mapping as an adjunct to their purple blobs.

Related Articles:
When good ground control is indispensable: two field examples.
Closing the discovery gap